285661020 has 48 divisors (see below), whose sum is σ = 827436960. Its totient is φ = 73549056.

The previous prime is 285661007. The next prime is 285661021. The reversal of 285661020 is 20166582.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285661021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80347 + ... + 83826.

It is an arithmetic number, because the mean of its divisors is an integer number (17238270).

Almost surely, 2^285661020 is an apocalyptic number.

285661020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

285661020 is an abundant number, since it is smaller than the sum of its proper divisors (541775940).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

285661020 is a wasteful number, since it uses less digits than its factorization.

285661020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164214 (or 164212 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 285661020 is about 16901.5094000506. The cubic root of 285661020 is about 658.5928237675.

The spelling of 285661020 in words is "two hundred eighty-five million, six hundred sixty-one thousand, twenty".